Heat exchanger and turbulator retainer therefor



Dec. 1, 1959 D. w. CHRISTENSEN 2,915,294

HEAT EXCHANGER AND TURBULATOR RETAINER THEREFOR Filed March 19, 1958 /N VE N TOR B ATTORNEYS.

1M M 11/1! A.

United States Patent HEAT EXCHANGER AND TURBULATOR RETAINER THEREFOR Donald W. Christensen, Racine, Wis., assignor to Young Radiator Company, Racine, Wis., a corporation of Wisconsin Application March 19, 1958, Serial No. 722,478 2 Claims. (Cl. 257-124) This invention relates to retainers for holding in place the turbulators for multi-tube heat exchangers.

In certain types of heat exchanger, especially those with multiple small-diameter cores often used in the cooling of oil, internal turbulators are placed in the tubes to break up the concentric laminae flow through the tubes, and thereby increase the heat dissipation. In many cases these turbulators require occasional removal for washing and permitting flushing of the tubes. With heat exchangers of this type, there has always been a problem of retaining the turbulators against axial shifting in the tubes. The use of wires is a common expedient for this purpose. However, considerable labor is required to do the initial wiring and later to remove, and subsequently replace, the wiring to permit the removal of the turbulators. found expensive and not wholly satisfactory.

The main objects of this invention, therefore, are to provide an improved form of retainer for holding turbulators in operative position in multi-tube heat exchanger cores; to provide an improved turbulator-retainer which may be dimensioned to fit in practically any size and/or shape of tank; to provide an improved turbulator-retainer of this kind which creates no appreciable resistance to the flow of fluid through the heat exchanger core; to provide an improved turbulator-retainer of this kind which is self-positioning and requires no fasteners to hold the retainer in place in a tank; to provide an improved turbulator-retainer of this kind which cannot be displaced in the tank nor allow the turbulators to be displaced regardless of any position which the heat exchanger may assume in the course of shipment or use; to provide an improved turbulator-retainer of this kind which can be used with either one or both tanks of a heat exchanger; and to provide an improved turbulator-retainer of this kind which is simple in construction, hence economical to manufacture, and which is easily positioned when the unit is initially assembled at the factory and easily removed and replaced by the user of the heat exchanger when it is necessary to flush the tubes and clean the turbulators.

In the adaptation shown in the accompanying draw- Fig. 1 is a plan view of a turbulator-retainer constructed in accordance with this invention;

Fig. 2 is a side elevation of the same;

Fig. 3 is an end elevation of the same;

Fig. 4 is an enlarged, transverse, sectional view of a tank and the connected end of a heat-exchanger core showing in position a turbulator-retainer of the type shown in the other views; and

Fig. 5 is a further enlarged, fragmentary, cross-sectional view of the tank taken on the plane of the line 5-5 of Fig. 4.

The essential concept of this invention involves a perforate, shallow, channel-shaped member, of a length and width but slightly less than that of the tank wherewith it is to be used, positioned on the tube-supporting header Other expedients have been- 2,915,294 Patented Dec. 1, :1959

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of the heat-exchanger to space a transverse perforate base part of the member closely above the open ends of the tubes, the member being held in such position by a plurality of upright brackets of a height substantially equal to depth of the tank,with which the heat-exchanger is normally equipped, whereby the member is secured in place by contact of the brackets against the closed top of the tank.

The general character of a heat exchanger 6, with which a turbulator-retainer 7 embodying the foregoing concept is designed for use, involves a plurality of parallel tubes 8 the opposite ends of which are bonded by headers 9 whereto is secured a tank 10.

As here shown, the tubes 8 are round and each has inserted therein a turbulator 11 of desired form. It is the securing of these turbulators 11in operative relationship in the tubes that the retainer 7 has been'developed, as presently will be set forth.

In the type of heat exchanger 6 here shown, the header 9 is integral with the tank 10. The open top of the tank It) is closed by a plate 12 secured by bolts 13 to an outwardly disposed, perimetrical flange 14 integral with the upper end of the tank 10. Other header-tank combinations have the header in the form of a shallow flanged plate with a tank of U-shaped cross-section bolted to the header.

Whatever the type of heat exchanger, the header-tank assembly may be the same at both ends of the core unit or they may be somewhat different at the opposite ends of the core unit. In any event it is imperative that the turbulators, if used, remain in operative relationship in the tubes 8 regardless o f the position in which the heat exchanger maybe placed," in use 'or in shipment, and regardless of the pressure flow of the fluid through the tubes 8, when the exchanger is in service. To the end of keeping the turbulators 11 properly in the tubes 8, various expedients heretofore have been resorted to by heat exchanger manufacturers. The most common expedient has been the use of wires tying together the exposed ends of the turbulators. Such an expedient is costly in labor to the manufacturer, in the first instance, and to the user in unwiring when it becomes necessary to remove the turbulators to permit their cleaning and the flushing of the tubes.

The turbulator retainer 7, constructed in accordance with this invention, comprises a member 15 and brackets 16.

As here shown, the member 15 is of shallow, channelshape with a base part 17 perforated with a series of apertures 18. In length and width, the member 15 is but slightly less than the inside length and width of the header 9. The member 15 is dimensioned as to permit the short parallel leg parts 19 to rest on the header 9. along its interior lateral edges and space the perforate base part 17 a short distance above the ends of the tubes 8.

The apertures 18 are smaller in diameter than the tubes 8 and are more closely spaced than are the tubes 8, as will be most apparent from Fig. 5. Also, the positioning of the apertures 18 is such that no aperture 18 is ever alined with any tube 8. The many more apertures 18 than tubes 8 insures so free and unrestricted flow of the fluid between tubes 8 and the tank '10 as to reduce to a very minimum, if not completely eliminate, turbulation of the fluid at these areas.

The brackets 16 are U-shaped strips of metal inverted ly positioned with the extremities of the parallel arms 20 bonded to the opposite leg parts 19 of the member 15 and with the transverse cross-piece 21 opposedly spaced from the base part 17 of the member 15. The length of the arms 20 is substantially the same as the inside depth of the tank 10. Thus, with the leg parts 19 resting on the tube header 9 the cross-piece 21 is in contact with the top of the tank 10, which, in the type of heat exchanger shown herein, is the plate 12. Two or more of these brackets 16 are positioned longitudinally along the member 15.

From the foregoing description it will be obvious that a turbulator-retainer, constructed in accordance with this invention, will be dimensioned to conform with the interior dimensions and contour of the header-tank assembly of the heat-exchanger with which the retainer is to be used. Also as is apparent from the drawings and description, such a retainer is easily placed in position initially by the manufacturer of the heat exchanger. Moreover, the user of a heat exchanger with such a retainer will find it simple and economical to remove the retainer to permit the withdrawal of the turbulators for cleaning and flushing of the tubes. This being efiected it is equally simple and economical to replace the turbulators and the retainer.

Variations and modifications in the details of structure and arrangement of the parts may be resorted to within the spirit and coverage of the appended claims.

I claim:

1. In combination with a heat exchanger involving a multi-tube core unit having the tube ends bonded to a header mounting a tank and having turbulators removably arranged in the tubes, a turbulator-retainer comprising, a channel-shaped member of a length and width enough less than the internal length and width of the tank to loosely fit in the tank with the transverse parallel parts of the member resting on the header, the base part of the member being perforate with holes of diameters less than the internal diameters of the tubes and positioned in disalignment with the tubes, and brackets secured to the member normal to the perforate base part and of a 4 length to dispose their outer ends in contact with the wall of the tank opposed to the supporting header when the member is resting on the header and unattached thereto, whereby the turbulators are retained against displacement in the tubes when the tank and header are secured in their operative relationship.

2. In combination with a heat exchanger involving a multi-tube core unit for vertically-disposed use having the tube ends bonded to a header mounting a tank and having turbulators removably arranged in the tubes, a turbulator-retainer comprising, a channel-shaped member of a length and width enough less than the internal length and width of the tank to loosely fit in the tank with the transverse parallel parts of the member resting on the header, the base part of the member being perforate with holes of diameters less than the internal diameters of the tubes and positioned in disalignment with the tubes, and a plurality of U-shaped brackets of an external Width transversely of the parallel parts less than the transverse internal width of the tank and of a References Cited in the file of this patent UNITED STATES PATENTS Meurk et al. Mar. 15, 1932 Shutt et al. Oct. 19, 1954 

